Question

a car can cover 300km in 3hours, if it's speed decrease d by 12kmph
How much time does the car take
to cover
a distance
of440kmph
apo kom?
c. 6 hours
A. 8 hours
B 5 hours
D. None of these​

Answer 1

Explanation:

Let speed of car be x km/h.

and total time in journey be 't'

then

Given x=

t

300

xt=300-----(1)

and if speed =x+10

time=t-1

x+10=

(t−1)

300

(x+10)(t-1)=300---(2)

xt-x+10t-10=300

10t-x=310-300=10

10t-x=10

10t-

t

300

=10

10t

2

−10t−300=0

t

2

−t−30=0

(t-6)(t+5)=0

t=6 & t



=−5

if t=6 then x=

6

300

=50

speed of car be 50 km/h

and time journey be 6 hrs.

Answer 2

Answer:

speed =300 ÷3 =100 kmph

decreased by 12kmph =88 kmph

time = 440 ÷88 = 5hrs